Blow-out preventer



June 6, 1967 R. W. WALKER BLOW-OUT PREVENTER Filed Feb. 1 1965 2 Sheets-Sheet 1 20 2? INVENTOR. RfiYMO/VD m m1. KEQ.

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June 6, 1967 R. w. WALKER BLOW-OUT PREVENTER 2 Sheets-Sheet 2 Filed Feb.

m RM /.,M N f w 0 Y B A e United States Patent 3,323,773 BLOW-BUT PREVENTER Raymond W. Walker, Huntington Beach, Calif., assiguor to Shaffer Tool Works, Brea, Caiif., a corporation of California Filed Feb. 1, 1963, Ser. No. 255,430 6 Claims. (Cl. 251-11 The present invention relates to an improved blow-out preventer device and more particularly to a blow-out preventer device utilizing a mass of resilient sealing material adapted to be rolled into a sealing position completely closing off a well hole with or without a drill string therein.

Blow-out preventer devices of various types are well known in the oil Well industry. Many of the blow-out preventers now in use have unique characteristics which prohibit their use in some situations. In offshore sub-sea drilling operations, the blow-out preventer is attached to the well head under water. When an emergency arises, such as a storm, the preventer is generally required to be actuated to seal the well hole even when the drill pipe cannot be removed. A manually operated blow-out preventer in such circumstances would be impractical as a diver would be required to actuate the preventer. Consequently, a blow-out preventer that can be remotely operated from the derrick floor or the ship deck is highly desirable.

Ram-type blow-out preventers are rather complicated and require a plurality of sealing elements and control valves in order to completely seal off the well hole when different diameter drill stringsare used. During the confusion of an emergency, the more complicated control valves ofier greater chances of mistakes and errors. In offshore sub-sea drilling, emergencies occur frequently and it would be more convenient to use a blowout preventer which is less complicated to operate and lessens the chances of error.

Some blow-out preventers are provided with rubber or resilient seals adapted to be moved between sealing and non-sealing position. However, such devices operate on a sliding rubber theory wherein the rubber seal is slid along a wedged surface to effectuate a seal. By so doing, the sliding rubber surface is subjected to constant wear and the possibility of ultimate failure at that point. This same device may effectuate a seal at the sealing surface but a constant vertical movement or rotational movement tends to wear the sealing surface.

The device of the present invention provides a blow-out preventer that obviates all of the undesirable characteristics of the devices described heretofore. The present device includes a resilient sealing means and translating means for converting axial movement of the resilient sealing means into a rolling inward motion to completely seal the well hole with or without a drill string within the device. Such translating means provides a metal-to-metal sliding translating surface with the housing of the blowout preventer device to insure a reliable device capable of constant sealing and releasing motion Without failure at that point. The device of the present invention provides a greater sealing surface at one end of the seal due to the metallic translating means arranged in such a way as to reinforce the seal while in its sealing position. As the seal wears, more and more material is adapted to be wedged into the sealing position wherein the seal becomes more effective the longer it remains in operation.

Accordingly, it is a general object of the present invention to provide a blow-out preventer device that avoids all of the foregoing disadvantages of blow-out preventers used heretofore.

An object of the present invention is to provide a blowout preventer that will seal ofl? a well When a drill string has been removed as well as closing off a well when a 3,323,773 Patented June 6, 1967 drilling string remains therein without having to replace the sealing element.

Another object of the present invention is to disclose and provide a blow-out preventer that can be remotely operated.

Another object is to provide a blow-out preventer having a resilient sealing means adapted to be rolled into and out of sealing position with a minimum of wear.

.Still another object of the present invention is to disclose and provide a blow-out preventer wherein the sealing element can remain in its sealing position even when the drilling string is rotated or moved axially.

Other objects and advantages of this invention will be readily apparent from the following description when considered in connection with the appended drawings.

In the drawings:

FIG. 1 is a diagrammatic view of sub-sea drilling rig in which the blow-out preventer device of the present invention may be utilized.

FIG. 2 shows a longitudinal section of an exemplary embodiment of the device of the present invention in the open and non-sealing osition with a drilling string within the device.

FIG. 3 shows a transverse section of the device taken along plane IIIIII of FIG. 2.

FIG. 4 is a longitudinal section of the device similar to FIG. 2 with the device in the sealed position around the drilling string.

FIG. 5 is a longitudinal section of another embodiment of the device with the seal in a plurality of sections and in a completely closed and sealing position with no drilling string therein.

FIG. 6 is a transverse section of the device in sealing position with a drilling string therein taken along plane VIV1 of FIG. 4.

FIG. 7 is a transverse section of the other embodiment of the device in sealing position with no drilling string therein taken along plane VII-VII of FIG. 5.

Referring now to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in FIG. 1 an exemplary blow-out preventer device 10 of the present invention as used in offshore sub-sea drilling rigs. It is understood that device 1%) of the present invention may be used in all types of drilling rigs whether they are underwater or not.

The blow-out preventer 10 as seen in FIG. 2 is a preferred embodiment of the present invention and may have a metallic housing 11 including an upper portion 12 and lower portion 13 detachably secured together by a ring clamp 14. Bolts 14a may be removed from ring clamp 14 and housing portions 12 and 13 to allow the housing to be disassembled to replace the sealing element therein if necessary. The housing 11 may be connected within a drilling rig between the various subs or assemblies but generally it is positioned immediately above the well hole.

Axially aligned well-tool receiving ports 15 and 16 are provided in the upper portion 12 and lower portion 13, respectively, of the housing 11 for receiving a welltool or drilling string 17 adapted to be axially moved within the device 10. Within the housing 11, and preferably inside the upper housing portion 12, is provided an enlarged cylindrical bore 18 and a curved inner surface 19 having a spherical zone form extending from the port 15 toward the bore 18. The port 15 and the upper edge of the curved inner surface 19 meet at an annular edge 20 within the housing 11.

A resilient sealing means 21 is positioned within the enlarged cylindrical bore 18 and is adapted to be selectively moved between non-sealing position as shown in 3 FIGS. 2 and 3 and a sealing position as shown in FIGS. 4 and 6 with the drill string 17 not removed and in FIGS. and 7 with the drill string 17 removed.

Such sealing means 21 may include a continuous ring of resilient material such as natural or synthetic rubber, and it has been found that Hycar-Buna having a Shore hardness between 5080 is particularly well suited for such a seal. The resilient ring 21 in FIGS. 2, 3, 4 and 6 includes an inner bore 22 and outer surface 23 and in the normal non-sealing position of FIGS. 2 and 3 the diameter of the inner bore 22 of the seal 21 is approximately equal to the diameter of the bores 15 and 16. The seal 21 is adapted to cooperate with the curved inner surface 19 of the housing 11 for movement between sealing and non-sealing positions to prevent fluid within a well hole from being vented to the atmosphere.

Translating means are provided for slidably cooperating with the curved inner housing surface 19 and cooperating with the sealing means 21 for converting axial movement or pressure on the sealing means into a roll ing inward motion whereby maximum inward sealing motion is attained by the sealing ring 21 adjacent the Well-tool receiving port 15. Such translating means may include a plurality of curved metallic shoes 24 bonded to the outer surface 23 of the sealing ring 21.

Each of the metallic shoes 24 has an inwardly protruding flange 25 integrally connected with the shoe 24 and provided with openings 25a therein. The outer curved surfaces on each of the shoes 24 substantially conform to the curved inner surface 19 of the housing 11 and are adapted to provide surfaces having a minimum of sliding frictional contact during movement therebetween.

It is preferred that the resilient ring 21 and shoes 24 are molded together as a unit and assembled within the housing 11. In the event of wear, the entire unit of the ring 21 and shoes 24 can be easily replaced by another similar unit.

In the normal non-sealing position the shoes 24 are so constructed as to be spaced from each other and tend to contract and move toward each other to form a reinforcing wall when the seal 21 is moved into the sealing position as seen in FIGS. 6 and 7.

Remotely controlled and axially movable actuating means are positioned in the enlarged bore 18 and connected to the sealing means 21 for applying an axial movement to the sealing ring and for moving the sealing means 21 toward and away from the curved inner housing surface 19 between closed sealing and open non-sealing positions. Such actuating means may include a hollow piston 27 axially positioned within the housing 11 and having an inner bore 27a of substantially the same diameter as ports 15 and 16.

The piston 27 may include a transversely extending annular wall 28 having a surface 23a for contacting the sealing means 21 and stop surface 28b for positioning the piston 27 in the non-sealing position.

An inwardly extending, stationary annular partition wall 29 is provided within housing 11 and is adapted to slidingly contact and receive the piston 27. The partition wall 29 separates the enlarged bore 18 from a chamber 30 provided within the lower housing portion 13. The partition wall 29 includes a lower stop surface 29a and upper stop surface 29b adapted to engage the wall surface 28b.

A laterally extending stop flange 31 is provided on the end of the piston 27 and includes a stop surface 31:: adapted to engage lower stop surface 29a on partition wall 29 to limit movement of the piston 27 when actuated into the sealing position.

Suitable O-rings or other fluid sealing means 32 are provided on the piston 27, walls 28 and 29 and flange 31 to provide fluid-tight sliding connections between these elements and piston 27 A fluid actuating port 33 may be provided through the lower housing portion 13 and stationary partition wall 29 and opens through the upper stop surface 29b into the enlarged bore 18. A fluid return port 34 may also be provided through the lower housing portion 13 and stationary partition wall 29 and opens through the lower stop surface 29a into the chamber 30.

Remotely controlled compressed fluid sources and controls (now shown) are adapted to be connected to the fluid ports 33 and 34 for actuating the piston 27 between sealing and non-sealing positions.

The piston 27 and sealing means 21 may be connected for simultaneous movement by various means. As shown best in FIGS. 2 and 4, an annular connecting ring 35 may be molded within the resilient means 21 during manufacture and have an inner threaded surface 35a of such connecting ring 35 exposed. The upper portion of piston 27 may be provided with a threaded portion adapted to threadedly receive the threaded surface 35a of connecting ring 35 to positively connect resilient means 21 to piston 27 The connecting ring 35 is preferably mounted in the resilient means 21 above and in contact with the lower ends of each of the shoes 24.

It is understood that other means may be used to connect the piston 27 with the sealing means 21.

The piston 27 when actuated upwardly into the sealing piston only contacts the lower portion of the resilient sealing means 21 and does not directly engage the shoes 24. The entire mass of material of sealing means 21 is moved when axial pressure is applied thereto by the piston 27 and such axial movement of the sealing means 21 is translated into a rolling inward motion by the motion translating shoes 24 cooperating with the curved inner housing surface 19.

FIGS. 5 and 7 show a different embodiment of the blow-out preventer of the present invention and differs primarily from the device 10 shown in FIGS. l4 and 6 in the connection between the upper and lower housings 12 and 13 and the resilient sealing means 21. Like elements in the device 10 in FIGS. 5 and 7 are designated with the same reference numeral as used in the description of device 10 in FIGS. 1-4 and 6. Modified elements in device 10' in FIGS. 5 and 7 are designated with similar reference numerals as used in FIGS. I4 and 6, including the addition of a prime designation.

The housing 11' includes an upper housing portion 12' and a lower housing portion 13' threadedly connected to gether rather than detachably secured together by means of the clamping ring 14. To replace or insert the sealing means 21 within the housing 11', the upper and lower housing portions 12 and 13 are easily disconnected but require relative rotation between the housing portions.

The resilient sealing means 21' is substantially the same as the resilient means 21 but, as best seen in FIG. 7, comprises a plurality of sections 21a and 21b rather than a single continuous sealing ring. The shoes 24 are still preferably molded to each of the resilient sealing means sections 21'a and 21b in the same manner as described above and also are used to translate the axial movement of the sealing means 21' into a rolling inward motion to obtain a miximum inward sealing action adjacent the port 15.

It has been found that a split resilient sealing means 21' comprising a plurality of sections has certain advantages over a continuous sealing ring. When the sealing means is required to be replaced and the'drill string cannot be removed from the well hole, a split resilient means 21' can be assembled around the drill string and inserted within the housing 11. The plurality of the resilient seal sections 21a and 21b when actuated into the sealing position by the actuating piston 27 provides the same sealing action as the continuous resilient sealing means 21.

The operation of the blow-out preventer devices 10 and 10' of the present invention is simple, positive and efficient. Compressed air or fluid is introduced into the port 33 for contact with the surface 2% of the piston wall 29 causing upward movement of the piston 27. Piston 27 is sesa e thus moved axially toward the curved inner surface 19 of the housing 11, and an axial pressure is thus applied to the resilient sealing means 21 and 21'. The entire mass of resilient material of means 21 and 21 is therefore displaced upwardly, causing the shoes 24 to slidably engage the inner curved housing surface 19. The shoes 24, due to their cooperation with the inner housing Wall, move upwardly and inwardly to translate the axial motion of the sealing means 21 and 21 into an inward rolling motion forcing the sealing means into a sealing position.

When it is desired to return the sealing means into the non-sealing position as shown in FIGS. 2 and 3, pressurized fluid is provided through fluid port 34 into chamber 30 and such fluid acts against the stop flange surface 31a to force the piston 27 downwardly. The fluid pressure in fluid port 33 is released, and port 33 functions as a vent to relieve the fluid within the enlarged bore 18 between the piston wall 28 and stationary wall 29.

It is understood that the blow-out preventer and 10 can therefore completely seal off a well hole with or without a drill string 17 therein. The metal-on-metal translation between the curved shoes 24 and the inner housing surface 19 of the axial force on the resilient means into inwardly directed rolling motion provides a uniform and positive translating action. Sealing means 21 is thus compressed uniformly into the sealing position as the axial pressure is translated into an inward rolling force. The reinforcing action of the curved metal translating shoes 24 provides a maximum sealing surface adjacent the well-tool receiving port 15. As the sealing means 21 wears, material within the resilient seal 21 is forced inwardly into the sealing position due to the flexibility and resilient properties of the sealing means 21. In addition, the non-metallic contact between the piston 27 and the shoes 24 aids in continously urging the resilient material of the sealing means 21 inwardly as wear occurs.

Moreover, as the pressure in the well hole increases, the increased pressure tends to further actuate the piston 27 and provide additional pressure on the sealing means 21 to strengthen the seal and provide a self-pressure actuating means when suflicient pressure is developed within the well hole.

It can therefore be seen that the resilient sealing means 21 is actuated between sealing and non-sealing positions with a minimum of frictional contact with the housing surfaces and with a minimum of wear. This produces a sealing element of longer life and therefore requires infrequent replacement. The rolling action of the sealing means during movement between the sealing and non-sealing positions tends to provide a novel sealing action which tends to be more efficient and positive than prior seals used heretofore in blow-out preventers.

The blow-out preventer of the present invention will seal off well holes having drill strings therein of various diameters ranging from zero diameter up to the diameter of the welltool receiving ports. A variety of oddly shaped mandrels can also be sealed off including a square Kelly mandrel or one that is polygonally shaped.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

I claim:

1. A selectively adjustable blow-out preventer adapted for use in oil well rigs, comprising:

a stationary metallic housing including detachable upper and lower housing sections provided with opposing axially aligned well-tool receiving ports,

an enlarged cylindrical bore within said housing,

a curved inner surface of substantially spherical zone form extending from one of said well-tool receiving ports toward said enlarged cylindrical bore,

a resilient sealing ring within said housing having a central bore and an outer surface portion adapted to oo- 6 operate with said curved inner surface of said housing for selective adjustable movement between a nonsealing position and a closed sealing position whereby fluid within the well hole is prevented from being vented to the atmosphere,

remotely controlled and axially movable actuating means positioned in said enlarged bore and connected to said sealing ring for applying an axial movement to said sealing ring and for moving said sealing ring toward and away from said curved inner surface of said housing between closed sealing and open nonsealing positions,

and a plurality of curved metallic translating means bonded to said sealing ring and having exposed surfaces adapted to slidably contact said curved inner surface of said housing for translating the axial movement of said actuating means into a rolling inward motion of said sealing ring whereby maximum inward sealing motion is attained by said ring adjacent said well-tool receiving ports,

whereby said sealing ring is adapted to completely close off a well when the drilling string has been removed as well as closing off a well when a drilling string reremains therein.

2. A selectively adjustable blow-out preventer adapted for use in oil Well rigs, comprising:

a stationary metallic housing provided with an axially aligned well-tool receiving port,

an enlarged cylindrical bore within said housing,

a curved inner surface of substantially spherical zone form extending from said well-tool receiving port toward said enlarged cylindrical bore,

resilient sealing means Within said housing having a central bore and an outer surface portion adapted to cooperate with said curved inner surface of said housing for selective adjustable movement between a nonsealing position and a closed sealing position whereby fluid within the well hole is prevented from being vented to the atmosphere,

axially movable actuating means positioned in said enlarged bore and connected to said sealing means for applying an axial movement to said sealing means and for moving said sealing means toward and away from said curved inner surface of said housing between closed sealing and open non-sealing positions.

and a plurality of curved metallic translating means bonded to said sealing means and having exposed surfaces adapted to slidably contact said curved inner surface of said housing for translating the axial move ment of said actuating means into a rolling inward motionof said sealing ring whereby maximum inward sealing motion is attained by said ring adjacent said well-tool receiving port,

whereby said sealing means is adapted to completely close off a well when the drilling string has been removed as well as closing off a well when a drilling string remains therein.

3. A selectively adjustable blow-out preventer adapted for use on oil well rigs, comprising:

a stationary housing provided with an axially aligned well-tool receiving port,

an enlarged cylindrical bore within said housing,

a curved inner surface of substantially spherical zone form extending from said well-tool receiving port toward said enlarged cylindrical bore,

resilient sealing means within said housing having an inner bore and an outer surface portion adapted to cooperate with said curved inner surface for selective adjustable movement between a non-sealing position and a closed sealing position whereby fluid within the well hole is prevented from being vented to the atmosphere,

axially movable actuating means positioned in said enlarged bore and connected to said sealing means for applying axial movement to said sealing means and for moving said sealing means toward said curved inner surface of said housing,

and a plurality of curved metallic translating means bonded to said sealing means and having exposed surfaces adapted to slidably contact said curved inner surface of said housing for translating the axial movement of said actuating means into a rolling inward motion of said sealing ring whereby maximum inward sealing motion is attained by said ring adjacent the well-tool receiving port,

whereby said sealing ring is adapted to completely close off a well when the drilling string has been removed as well as closing ofl a well when a drilling string remains therein.

4. A selectively adjustable blow-out preventer adapted for use on oil well rigs, comprising:

a stationary housing provided with an axially aligned well-tool receiving port,

an enlarged cylindrical bore within said housing,

a curved inner surface of substantially spherical zone form extending from said well-tool receiving port toward said enlarged cylindrical bore,

resilient sealing means within said housing having an inner bore and an outer surface portion adapted to cooperate with said curved inner surface of said housing for selective adjustable movement between a non-sealing position and closed sealing position whereby fluid within the well hole is prevented from being vented to the atmosphere,

axially movable actuating means positioned in said enlarged bore and connected to said sealing means for applying an axial movement to said sealing means and for moving said sealing means toward said curved inner surface of said housing,

and translating means slidably cooperating with said curved inner surface of said housing and cooperating with said sealing means for converting axial movement of said actuating means into a rolling inward motion of said sealing means whereby maximum inward sealing motion is attained by said ring adjacent the well-tool receiving port.

5. A selectively adjustable blow-out preventer adapted for use on oil well rigs, comprising:

a stationary housing provided with an axially aligned well-tool receiving port,

a curved inner surface of substantially spherical zone form extending from said well-tool receiving port,

resilient sealing means within said housing having an inner bore and an outer surface portion adapted to cooperate with said curved inner surface of said housing for selective adjustable movement between a non-sealing position and closed sealing Position whereby fluid within the well hole is prevented from being vented to the atmosphere,

axially movable actuating means connected to said sealing means for applying an axial movement to said sealing means,

and translating means slidably cooperating with said curved inner surface of said housing and cooperating with said sealing means for converting axial movement of said actuating means into a rolling inward motion of said sealing means whereby maximum inward sealing motion is attained adjacent the welltool receiving port.

6. In a selectively adjustable blow-out preventer adapted for use on oil well rigs, the provision of a stationary housing provided with an axially aligned well-tool receiving port,

a curved inner surface of substantially spherical zone form extending from said well-tool receiving port,

resilient sealing means within said housing and adapted to move axially to cooperate with said curved inner surface of said housing for selective adjustable movement between a non-sealing position and a sealing position whereby fluid within the well hole is prevented from being vented to the atmosphere,

translating means slidably cooperating with said curved inner surface of said housing and cooperating with said sealing means for converting axial movement of said resilient sealing means into a rolling inward motion of said sealing means whereby maximum inward sealing motion is attained adjacent the Welltool receiving port.

References Cited UNITED STATES PATENTS 2,233,041 2/1941 Alley 251-1 X 2,287,205 6/ 1942 Stone 27728 2,529,744 11/ 1950 Schweitzer 277-73 2,731,281 1/1956 Knox 27773 X 2,760,750 8/ 1956 Schweitzer 251-1 WILLIAM F. ODEA, Primary Examiner.

M. CARY NELSON, R. GERARD, Assistant Examiners. 

1. A SELECTIVELY ADJUSTABLE BLOW-OUT PREVENTER ADAPTED FOR USE IN OIL WELL RIGS, COMPRISING: A STATIONARY METALLIC HOUSING INCLUDING DETACHABLE UPPER AND LOWER HOUSING SECTIONS PROVIDED WITH OPPOSING AXIALLY ALIGNED WELL-TOOL RECEIVING PORTS, AN ENLARGED CYLINDRICAL BORE WITHIN SAID HOUSING, A CURVED INNER SURFACE OF SUBSTANTIALLY SPHERICAL ZONE FORM EXTENDING FROM ONE OF SAID WELL-TOOL RECEIVING PORTS TOWARD SAID ENLARGED CYLINDRICAL BORE, A RESILIENT SEALING RING WITHIN SAID HOUSING HAVING A CENTRAL BORE AND AN OUTER SURFACE PORTION ADAPTED TO COOPERATE WITH SAID CURVED INNER SURFACE OF SAID HOUSING FOR SELECTIVE ADJUSTABLE MOVEMENT BETWEEN A NONSEALING POSITION AND A CLOSED SEALING POSITION WHEREBY FLUID WITHIN THE WELL HOLE IS PREVENTED FROM BEING VENTED TO THE ATMOSPHERE, REMOTELY CONTROLLED AND AXIALLY MOVABLE ACTUATING MEANS POSITIONED IN SAID ENLARGED BORE AND CONNECTED TO SAID SEALING RING FOR APPLYING AN AXIAL MOVEMENT TO SAID SEALING RING AND FOR MOVING SAID SEALING RING TOWARD AND AWAY FROM SAID CURVED INNER SURFACE OF SAID HOUSING BETWEEN CLOSED SEALING AND OPEN NONSEALING POSITIONS, AND A PLURALITY OF CURVED METALLIC TRANSLATING MEANS BONDED TO SAID SEALING RING AND HAVING EXPOSED SURFACES ADAPTED TO SLIDABLY CONTACT SAID CURVED INNER SURFACE OF SAID HOUSING FOR TRANSLATING THE AXIAL MOVEMENT OF SAID ACTUATING MEANS INTO A ROLLING INWARD MOTION OF SAID SEALING RING WHEREBY MAXIMUM INWARD SEALING MOTION IS ATTAINED BY SAID RING ADJACENT SAID WELL-TOOL RECEIVING PORTS, WHEREBY SAID SEALING RING IS ADAPTED TO COMPLETELY CLOSE OFF A WELL WHEN THE DRILLING STRING HAS BEEN REMOVED AS WELL AS CLOSING OFF A WELL WHEN A DRILLING STRING REREMAINS THEREIN. 